Security & Crypto
The basics of keeping data safe: ciphers, hashing, passwords, encoding, and everyday online safety, with hands-on Python.
Every lesson runs real code in your browser, checked the moment you submit. No installing anything, no setup, no waiting.
Start Security & Crypto freeWhat this course covers
- What is Cybersecurity?
- Caesar Cipher: Secret Messages
- Substitution Ciphers: Letter Mapping
- XOR Cipher
- Encoding is NOT Encryption
- Hashing: Fingerprints for Data
- The Magic One-Way Door: How Apps Check Your Password Without Knowing It
- Passwords: Strong, Salted, Hashed
- Strong Random Passwords
- Why Password Length Matters
- Public-Key Cryptography
- HTTPS & TLS
- Two-Factor Authentication & TOTP
- Input Validation: Your First Line of Defense
- SQL Injection
- Cross-Site Scripting (XSS)
- CSRF: Forging Requests
- Online Safety: Be a Smart User
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